On track to become a one-stop shop for cloud-based developers and publishers, Amazon has extended its in-app purchasing API to include games for Mac, PC and Web platforms. This functionality, which was launched exclusively for Android apps last year increases the reach of Amazon’s billing system and will encourage developers to produce more for Amazon-native platforms including the Kindle Fire. Developers also stand to gain additional marketing opportunities, with in-app purchase items now able to appear on best seller lists and in recommendation campaigns.